View Full Version : How to loosen tight pipe fittings.

05-08-2006, 01:56 AM
There is an easy way to loosen those impossible pipe fittings and plugs.

Find a used candle, or a new one, heat up the fitting enough to melt the candle wax.
You don’t need to heat it crazy red hot or anything, a propane torch will work.
Heat the area so it will melt the wax and suck it into the threads.

It will amaze you how easy it will come apart then.

The Bio Fuel Clinic

05-08-2006, 01:56 PM
I'll have to give that a try one day..

Does it work on nuts and bolts also?

Legal Eagle
05-08-2006, 02:51 PM
Hmm, neat trick. I'll have to give it a go. Thanks for the tip.

05-09-2006, 03:20 AM
I have a valve I can't get off a propane tank, any suggestions that don't involve heating? I like your trick but I think I'll wait for a better time to try it.

05-09-2006, 12:57 PM
If you fill the tank with water you should be able to safely heat the fitting as needed.


05-09-2006, 06:39 PM
Make sure the tank is as empty as possible, then close the valve.

Cut the valve protector handle thing off the top using a grinder or saw.

Then use a length of rope (5mm 1.4" polypropelyne type seems to work well). This is going to be hard to explain, use a knott that will tighten when pressure is used againist it. I use a clove hitch to tie each end around the cylinder body.

But tie the clove hitches in different directions, ie a left and right handed cloves hitches, so that when the loop in between the hitches is pulled tight, both knotts will tighen against the cylinder.

Then stick a pry bar under the loop and a big pair of stilsons, and the valve WILL come out.

I should be taking the valves off a coupl eof cyclinders in the next few days I will take some pictures to show it.


05-09-2006, 09:27 PM
Most of the Americans on this site probably do not know what a "big pair of stilsons" are, sounds like something that fits into a G or an F cup bra rather than the adjustable pipe wrench that it is.

05-10-2006, 06:05 PM
Yeh, I wondered that as i wrote it, but I was in a hurry (needed to go and pick the kids up from school at the time).

Anyway, heres some photos:

the controversial stihlsons, 'dunno why they are called that, i think it was the main manufacturer at the time, you may know them as pipe wrenches (it makes more sense)


the rope and the 'pry bar and pipe wrench extension tube:


The cyclinders are about 4ft in circumference, so the rope needs to be about 30ft in length for this. Use clove hitch knot:


but wrap the loose end under the loop of the rope which will have the tension on a few times. Then fasten the other end onto the cylinder leaving a loop in the middle:


Then attach the wrench and bar as shown


The more force you put on the wrench, the more force on the bar, and the knot gets tighter and grips harder. The loose end being wrapped around the tension section of the rope prevents it from coming undone.

3 minutes later, both gas taps removed, and they were tight, very tight, as my daughter will tesify


Now to fill them with water and leave them a week or so before trying to weld them (i also tend to purge them with argon).


Any questins or better pictures needed let me know


05-10-2006, 07:26 PM
Don't try the attached method on a gas tank. I had a stuck water heating element to remove. Welding a bar to it, then hitting the end of the bar with a hammer worked just fine.

To prepare propane gas cylinders for welding in a hurry, remove the fitting, fill to the brim with boiling hot water, then add more heat to actually boil the water inside the tank. Cool, drain and dry, and it's ready. Live steam is used by the navy, but I don't have any at home, so this was the closest I could come up with.

05-12-2006, 06:19 PM
Tried the candle trick on a hitch ball yesterday. Ball had only been installed for a week but it had crome plating and I guess it galled. Anyway, no go, had to use a sawzall.

05-12-2006, 06:31 PM
and I guess it galled

That's what i hate about stainless steel as well. Galls very easily.

05-12-2006, 06:34 PM
The other thing that can be done when you have something stuck in a threaded hole - heat the body which contacts the female threads. They will expand and make it alot easier to get out whatever it is you need to unscrew.

05-13-2006, 04:36 AM
Expanding the hole is the logical and effective way to heat and loosen a fitting. The wax melt method can work by heating the internal fitting and using the heat to suck in the lubricant. The galled metal is like welding things together. No method of lubrication can help that.

The question posted about rusted bolts…I haven’t tried that, but I will.

Let’s experiment more and share our results.


05-13-2006, 04:58 AM
Yea, I tried a torch, ,thin oil, candle wax, three foot pipe wrench and swearing. Sawzall was the only answer.